Consolidated Statements of Net Loss and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
OPERATING EXPENSES
Research and development	$ 63,492	$ 34,269
General and administrative	19,512	8,961
Total operating expenses	83,004	43,230
Loss from operations	(83,004)	(43,230)
OTHER INCOME/(EXPENSES)
Interest and other income/(expenses)	1,976	(44)
NET LOSS	(81,028)	(43,274)
Other comprehensive income
Foreign currency translation	43	175
COMPREHENSIVE LOSS	$ (80,985)	$ (43,099)
Net loss per share attributable to common stockholders, basic and diluted	$ (2.30)	$ (1.50)
Weighted average common shares outstanding, basic and diluted	35,183,488	28,772,384